//
//  WelcomeViewController.swift
//  新浪微博
//
//  Created by 焦林生 on 15/11/9.
//  Copyright © 2015年 焦林生. All rights reserved.
//

import UIKit
import SDWebImage

class WelcomeViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()

        //异步加载用户头像
        iconView.sd_setImageWithURL(UserAccountViewModel.sharedUserAccount.avatarUrl, placeholderImage: UIImage(named: "avatar_default_big"))
        
        
    }
    //搭建界面   设置根视图
    override func loadView() {
        //直接使用背景图像作为根视图,不用关心图像的放缩问题
        view = backImageView
        
        setupUI()
    }
    //MARK: - 界面动画
   //视图已经显示,通常可以动画/键盘处理
    override func viewDidAppear(animated: Bool) {
        
        super.viewDidAppear(animated)
        
        //1 更改约束 改变位置
        iconView.snp_updateConstraints { (make) -> Void in
            make.bottom.equalTo(view.snp_bottom).offset(-view.bounds.height + 200)
        }
        
        //2 动画
        welcomeLabel.alpha = 0
        
        UIView.animateWithDuration(1.2, delay: 0, usingSpringWithDamping: 0.8, initialSpringVelocity: 10, options: [], animations: { () -> Void in
            
            //强制修改约束  自动布局的动画
            //如果希望提前更新约束,调用,更新当前已经修改过的约束
            self.view.layoutIfNeeded()
            
            }) { (_) -> Void in
                
                UIView.animateWithDuration(0.8, animations: { () -> Void in
                    self.welcomeLabel.alpha = 1
                    }, completion: { (_) -> Void in
                        
                        print("ok")
                        //发送通知
                        NSNotificationCenter.defaultCenter().postNotificationName(LJSwithchRootViewControllerNotification, object: nil)
                })
        }
    }
    

    //MARK: - 懒加载控件
    //背景图像
    private lazy var backImageView: UIImageView = UIImageView(imageName: "ad_background")
    //默认头像(占位符)
    private lazy var iconView: UIImageView = {
    
        let iv = UIImageView(imageName: "avatar_default_big")
        
        iv.layer.cornerRadius = 45
        iv.layer.masksToBounds = true
        
        return iv
    }()
    //欢迎标签
    private lazy var welcomeLabel: UILabel = UILabel(title: "欢迎归来", fontSize: 17)
    
   
}
// MARK: - 设置界面
extension WelcomeViewController {

    private func setupUI() {
    
        //1. 添加控件
        view.addSubview(iconView)
        view.addSubview(welcomeLabel)
        
        //2. 自动布局
        iconView.snp_makeConstraints { (make) -> Void in
            make.centerX.equalTo(view.snp_centerX)
            make.bottom.equalTo(view.snp_bottom).offset(-200)
            make.width.equalTo(90)
            make.height.equalTo(90)
            
        }
        welcomeLabel.snp_makeConstraints { (make) -> Void in
            make.centerX.equalTo(iconView.snp_centerX)
                make.top.equalTo(iconView.snp_bottom).offset(16)
            
        }
        
    }
}
